Air New Zealand says it has saved the enough fuel for 20 flights between Auckland and Los Angeles by plugging in to mains power while on the ground here during the past year.
Instead of using big Auxiliary Power Units in their tails, jets are running off mains power to run onboard lighting, air conditioning and mechanical systems at the gate when the main engines are off.
The airline estimates that during the past year it has saved 2.5 million litres of fuel using electricity rather than jet fuel to power its Boeing 777, 787-9 and Airbus A320 aircraft at departure gates at Auckland and Christchurch International Airports.
This collaboration with airports has cut the airline's annual APU use by a third since July 1 last year, saving more than 6 million kilograms of carbon – the equivalent of removing 1000 cars from the road.
Air New Zealand is the country's biggest single user of petroleum products and last year its carbon footprint grew by 5.1 per cent, lower than its 6.3 per cent capacity growth. This was mainly due to more efficient aircraft joining the fleet which Morgan said were where the step change in reducing its carbon impact could be made.
In its latest sustainability report it said an average annual fuel efficiency improvement of 1.5 per cent was equal to 49,000 tonnes of carbon, a greenhouse gas.
Air New Zealand chief operational Integrity and standards officer David Morgan said the switch to ground power for its international aircraft was just one measure the airline has in place to curb fuel use and minimise carbon impact. The forecast savings had exceeded expectations.
"While Air New Zealand's fleet is one of the most modern and fuel efficient globally, we must keep pushing ourselves to operate smarter – both on the ground, and in the air, through initiatives such as flight path and climb optimisation, and reducing weight on board.
The airline used on average about 150,000 litres of fuel an hour and that represented 99.5 percent of the airline's total carbon impact.
"Hunting down efficiencies is the top priority for our carbon reduction programme and it's fantastic to see new ground processes at Auckland and Christchurch achieve these significant savings."
Morgan said that during the Marsden Point pipeline crisis last year, where airlines operating out of Auckland were restricted to just 30 percent of standard fuel use, the switch to ground power saved enough fuel to operate 40 more domestic flights than it would have been able to otherwise.